System | Series | Stage | Age (Ma) | |
---|---|---|---|---|
Cretaceous | Lower | Berriasian | younger | |
Jurassic | Upper | Tithonian | 145.5–150.8 | |
Kimmeridgian | 150.8–155.7 | |||
Oxfordian | 155.7–161.2 | |||
Middle | Callovian | 161.2–164.7 | ||
Bathonian | 164.7–167.7 | |||
Bajocian | 167.7–171.6 | |||
Aalenian | 171.6–175.6 | |||
Lower | Toarcian | 175.6–183.0 | ||
Pliensbachian | 183.0–189.6 | |||
Sinemurian | 189.6–196.5 | |||
Hettangian | 196.5–199.6 | |||
Triassic | Upper | Rhaetian | older | |
Subdivision of the Jurassic system according to the IUGS, as of July 2009. |
The Oxfordian is, in the ICS' geologic timescale, the earliest age of the Late Jurassic epoch, or the lowest stage of the Upper Jurassic series. It spans the time between 161.2 ± 4 Ma and 155.7 ± 4 Ma (million years ago). The Oxfordian is preceded by the Callovian and is followed by the Kimmeridgian.[1]
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The Oxfordian stage was introduced into scientific writing by Alexandre Brongniart in 1827. The stage takes its name from the city of Oxford in England.
The base of the Oxfordian stage is defined as the point in the stratigraphic record where the ammonite species Brightia thuouxensis first appears. A global reference profile for the base (a GSSP) had in 2009 not yet been assigned. The top of the Oxfordian stage (the base of the Kimmeridgian) is at the first appearance of ammonite species Pictonia baylei.
In the Tethys domain, the Oxfordian contains six ammonite biozones:
Ornithischians of the Oxfordian | ||||
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Taxa | Presence | Location | Description | Images |
Oxfordian? Tithonian? | Chaoyang, Liaoning, China | A marginocephalian dinosaur from the Late Jurassic of China, belonged to the Ceratopsia, a group of primarily herbivorous dinosaurs with parrot-like beaks | ||
Upper Shaximiao Formation, Sichuan, China | A genus of stegosaur similar to Kentrosaurus | |||
Upper Shaximiao Formation, Sichuan, China | One of the smallest of the stegosaurids at 3-4 metres long (10-13 ft), Chungkingosaurus had at least five spikes on its thagomizer. It had a rather high and narrow skull and large, thick bony plates. | |||
England, France, Spain, Portugal | A large stegosaurid | |||
Shishugou Formation, Xinjiang, China | Either a hypsilophodont, or a less-derived ornithischian | |||
Dashanpu Formation, Sichuan, China | By extrapolation from the remains of possible species and other basal ornithopods, it was a herbivorous bipedal animal around 1.3 to 1.5 meters long (4.3 to 4.9 ft). It would have been a strong runner | |||
Junggar Basin, Xinjiang, China | A genus of stegosaurid | |||
Upper Shaximiao Formation, Sichuan, China | The best understood of the Chinese stegosaurs. It was around 7.0 meters (23 ft) long and 2 meters (7 ft) high, with a postulated weight of around 4 metric tons (4.4 short tons). | |||
Shishugou Formation, Xinjiang, China | A small, primarily bipedal herbivore, approximately 1.2 meters (4 ft) long, the oldest and most primitive ceratopsian known to science. |
Thalattosuchians of the Oxfordian | ||||
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Taxa | Presence | Location | Description | Images |
An opportunistic carnivore that fed on fish, belemnites and other marine animals and possible carrion. Metriorhynchus grew to an average adult length of 3 meters (9.6 feet), although some individuals may have reached lengths rivaling those of large nile crocodiles. | ||||
Theropoda of the Oxfordian | ||||
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Taxa | Presence | Location | Description | Images |
Upper Shaximiao Formation, Sichuan, China | Yangchuanosaurus shangyouensis reached about 7 meters long (23 ft) with a skull around 80 cm long (32 in). Its relative Y. magnus grew larger still: up to 10 meters long (33 ft) with a skull up to 1 metre (3 ft) in length. There was a bony knob on its nose and multiple hornlets and ridges, similar to Ceratosaurus. It had a massive tail that was about half its length. | |||
Upper Shaximiao Formation, China | Monolophosaurus was a medium sized predator that grew to at least 5.7 meters (19 ft) long. It had an odd, unique crest on its head which ran most of the length of the skull. |
Nautiloids of the Oxfordian | ||||
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Taxa | Presence | Location | Description | Images |
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Belemnites of the Oxfordian | ||||
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Taxa | Presence | Location | Description | Images |
Jurassic Period | ||
---|---|---|
Lower/Early Jurassic | Middle Jurassic | Upper/Late Jurassic |
Hettangian | Sinemurian Pliensbachian | Toarcian |
Aalenian | Bajocian Bathonian | Callovian |
Oxfordian | Kimmeridgian Tithonian |